Computed tomography-based classifications of posterior malleolar fractures and their inter- and intraobserver reliability: a comparison of the Haraguchi, Bartonícek/Rammelt, and Mason classifications.

INTRODUCTION: Complex ankle fractures often include fractures of the posterior malleolus. The most clinically relevant posterior malleolus fracture classifications are computed tomography (CT) based. These classifications aim to enable clear communication and help develop treatment strategies. This study investigates the inter- and intraobserver reliability of the Haraguchi, Bartonícek/Rammelt and Mason posterior malleolar fracture classifications. MATERIALS AND METHODS: CT scans of 113 patients with a mean age of 56.2 (SD ± 17.8) years and fractures involving the posterior malleolus were analyzed twice by 4 observers with different levels of training. The posterior malleolar fractures were classified according to Haraguchi et al., Bartonícek/Rammelt et al. and Mason et al. The intraobserver and interobserver reliabilities were determined by calculating Cohen's and Fleiss' kappa values. RESULTS: We found substantial multi-rater interobserver agreement for all three classifications. The Haraguchi classification 0.799 (CI 0.744-0.855) showed the highest agreement, followed by the Bartonícek/Rammelt 0.744 (0.695-0.793) and Mason 0.717 (CI 0.666-0.768) classifications. Subgroup analyses showed substantial to perfect agreement for the Haraguchi and substantial agreement for the Bartonícek/Rammelt and Mason classifications independent of observer expertise. The intraobserver reliability was perfect for three and substantial for one of the observers. However, the classifications have certain pitfalls and do not consider the number of fragments, articular surface impressions, or intercalary fragments. CONCLUSION: All classifications show substantial, if not perfect inter- and intraobserver reliabilities independent of observer level of expertise.

Current and Future Concepts for the Treatment of Impaired Fracture Healing.

Bone regeneration represents a complex process, of which basic biologic principles have been evolutionarily conserved over a broad range of different species. Bone represents one of few tissues that can heal without forming a fibrous scar and, as such, resembles a unique form of tissue regeneration. Despite a tremendous improvement in surgical techniques in the past decades, impaired bone regeneration including non-unions still affect a significant number of patients with fractures. As impaired bone regeneration is associated with high socio-economic implications, it is an essential clinical need to gain a full understanding of the pathophysiology and identify novel treatment approaches. This review focuses on the clinical implications of impaired bone regeneration, including currently available treatment options. Moreover, recent advances in the understanding of fracture healing are discussed, which have resulted in the identification and development of novel therapeutic approaches for affected patients.

[One and a half years of e-scooters in Hamburg]. / Eineinhalb Jahre E-Scooter ­ Zwischenbilanz in Hamburg: Teil 2: Unfallcharakteristika.

Background: Since the spread of the so-called electric scooters (e-scooters) through rental services in Hamburg as of June 2019, accidents due to the use of this means of transportation have been regularly registered. The most frequent injury patterns among e­scooter riders involved accidents concerning the upper extremities and the head. There was a relevant accumulation of drunk drivers among the injured persons. Objective: The aim of the study is to compare injury patterns in drunk versus non-drunk e­scooter riders who had an accident. Material and methods: Data from the Department of Trauma Surgery at the University Medical Center Hamburg-Eppendorf were retrospectively analyzed for accidents involving e­scooters and the resulting injury patterns. For this purpose, the gender, age, injury pattern of the persons, the course of the accident, and information on previous alcohol consumption were recorded descriptively for the period from June 2019 to December 2021. Results: Drivers were on average 32 (interval: 15-88 years) years old and those under the influence of alcohol were predominantly male (69.9%). Accidents occurred mainly in summer and at night. Common injury patterns were injuries to the face, head, and extremities. Conclusion: It should be noted that injuries to the face and head occurred more frequently under the influence of alcohol than in the cohort without alcohol. Education about the health and legal consequences of riding an e­scooter under the influence of alcohol should be provided to all users. In addition, wearing a helmet or banning driving at night are possible measures to reduce accidents associated with drunk riding.

Age-, sex-, and subregion-specific properties of distal fibular microarchitecture and strength: An ex vivo HR-pQCT study.

Despite its clinical relevance in the context of ankle fractures, little is known about the bone microarchitecture and strength of the distal fibula, especially regarding age-, sex-, and subregion-specific effects. To address this gap of knowledge, we obtained fibulae from 30 skeletally intact donors at autopsy (each 15 male and female), which were analyzed by high-resolution peripheral quantitative computed tomography including micro-finite element analysis. Scans were performed in a 7-cm volume of interest and evaluated in three subregions according to the Danis-Weber fracture classification. Group comparisons and linear regression analyses were applied to evaluate the effects of age, sex, and subregion. From distal to proximal, we observed an increase of cortical parameters and a decrease of trabecular parameters. Age was primarily associated with a cortical decrease in all subregions (Danis-Weber type A, B, and C) in women. While women showed a greater magnitude of decline, men also exhibited an age-associated decrease for some parameters, including cortical area and cortical thickness in the type C subregion. Stiffness and failure load were highest in the type C subregion in both women and men. A critical age-related decline in bone strength parameters in the type B subregion was observed in women, providing an explanation for the increased incidence of low-traumatic type B fractures in the elderly. Together, these findings extend the current understanding of distal fibular microarchitecture, likely explaining the epidemiologic features of distal fibula fractures and emphasizing the need for age-adapted treatment algorithms.

[Established classification systems of posterior malleolar fractures : A systematic literature review]. / Etablierte Klassifikationssysteme der posterioren Malleolus-Fraktur : Eine systematische Literaturübersicht.

BACKGROUND: Posterior malleolar fractures are found in almost 50% of all ankle fractures. The high clinical relevance of these joint fractures is explained by the significantly worse clinical and functional outcome. There is still a lack of unified opinion regarding the classification and treatment of these fractures. OBJECTIVE: The aim of this article is to provide a systematic literature review of clinical studies that investigated posterior malleolar fractures and classified them using one of the three established classifications according to Haraguchi, Bartonicek/Rammelt, or Mason. MATERIAL AND METHODS: PubMed was searched without time limits. The systematic literature search was performed according to the current criteria of Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA). The methodological quality of the included studies was quantified using the modified Coleman score. RESULTS: A total of 27 studies with a total of 2220 patients were included in this systematic literature review. Trimalleolar fractures showed a significantly less favorable prognosis than other ankle fractures. The quality of reduction was the most important prognostic factor for the clinical outcome. CONCLUSION: None of the three classifications examined has become established in the literature. Most of the classifications are weak or should not be used with respect to a derivable treatment algorithm or a prognosis with respect to the outcome. Only the classification according to Bartonicek/Rammelt is suitable to become established in the literature and in clinical practice due to its derivable treatment algorithm.

Risk factors and injury patterns of e-scooter associated injuries in Germany.

Since the introduction of widely available e-scooter rentals in Hamburg, Germany in June of 2019, our emergency department has seen a sharp increase in the amount of e-scooter related injuries. Despite a rising number of studies certain aspects of e-scooter mobility remain unclear. This study examines the various aspects of e-scooter associated injuries with one of the largest cohorts to date. Electronic patient records of emergency department admissions were screened for e-scooter associated injuries between June 2019 and December 2021. Patient demographic data, mechanism of injury, alcohol consumption, helmet usage, sustained injuries and utilized medical resources were recorded. Overall, 268 patients (57% male) with a median age of 30.3 years (IQR 23.3; 40.0) were included. 252 (94%) were e-scooter riders themselves, while 16 (6%) were involved in crashes associated with an e-scooter. Patients in non-rider e-scooter crashes were either cyclists who collided with e-scooter riders or older pedestrians (median age 61.2 years) who tripped over parked e-scooters. While e-scooter riders involved in a crash sustained an impact to the head or face in 58% of cases, those under the influence of alcohol fell on their head or face in 84% of cases. This resulted in a large amount of maxillofacial soft tissue lacerations and fractures. Extremity fractures and dislocations were more often recorded for the upper extremities. This study comprises one of the largest cohorts of e-scooter associated injuries to date. Older pedestrians are at risk to stumble over parked e-scooters. E-scooter crashes with riders who consumed alcohol were associated with more severe injuries, especially to the head and face. Restricted e-scooter parking, enforcement of drunk driving laws for e-scooters, and helmet usage should be recommended.

Intercalary fragments in posterior malleolar fractures: incidence, treatment implications, and distribution within CT-based classification systems.

INTRODUCTION: Complex ankle fractures frequently include the posterior malleolus (PM). Despite advances in diagnostic and treatment strategies, PM fracture involvement still predisposes to worse outcomes. While not incorporated into the most common PM fracture classifications, the presence of an intercalary fragment (ICF) complicates treatment. This study aims to describe the incidence, morphology, and location of ICFs in PM fractures. MATERIALS AND METHODS: A total of 135 patients with a mean age of 54.4 (SD ± 18.9) years and PM fractures were analyzed for the presence of an ICF. Patients with an ICF were compared to those without in terms of age, gender, and treatment received. Characteristics of the ICFs in terms of location and size were assessed. Furthermore, the presence of an ICF in relation to the PM fracture classification according to Haraguchi et al., Bartonícek/Rammelt et al., and Mason et al. was investigated. RESULTS: ICFs presented in 55 (41%) of the 135 patients. Patients with an ICF were younger, and the PM was more often operatively treated when compared to patients without an ICF. A posterolateral approach was used significantly more often in patients with an ICF. Almost all ICFs were found in the posterolateral (58%) and posterocentral (35%) regions. The majority of fragments were found in Bartonícek/Rammelt type 2 fractures, the most common fracture type. Bartonícek/Rammelt type 3 fractures had the highest relative frequency of ICFs. CONCLUSION: ICFs are frequently found in PM fractures; however, they are not incorporated into any of the common classifications. They are generally found in younger patients and associated with more complex PM fractures. As they can complicate reduction of the main fragment and may require direct exposure to restore joint congruency, ICFs should be considered in PM fracture classifications. Due to their location, the majority of ICFs are able to be accessed using a posterolateral approach.

Visualization of the distal tibial plafond articular surface using four established approaches and the efficacy of instrumented distraction: a cadaveric study.

PURPOSE: Direct visualization is a very effective method in accomplishing adequate articular surface reconstruction in fracture repair. This study investigates distal tibial plafond articular surface visibility using the anteromedial, anterolateral, posteromedial, and posterolateral approaches, the effect of instrumented distraction on visibility, and which zones of the articular surface are visible for each approach. METHODS: The anteromedial, anterolateral, posteromedial, and posterolateral approaches to the distal tibial plafond were performed on 16 cadaveric ankle specimens. The articular surface visualization for each approach was marked using an electrocautery device with manual and instrumented distraction. Articular surface visualization was photographically documented. Digital axial segmentation and quantitative analysis of the visualized distal tibial plafond articular surface were performed. RESULTS: With manual distraction, distal tibial plafond articular surface visualization, expressed in percent of overall articular surface, was limited to 9% (SD ± 9) for the anteromedial, 24% (SD ± 18) for the anterolateral, 26% (SD ± 10) for the posteromedial, and 30% (SD ± 18) for the posterolateral approaches. Using instrumented distraction significantly improved articular surface visualization in all instances (p < 0.001). The anteromedial approach visible articular surface increased to 63% (SD ± 13), the anterolateral to 72% (SD ± 22), the posteromedial to 62% (SD ± 11), and the posterolateral to 50% (± 17). CONCLUSION: This study demonstrates the efficacy of instrumented distraction when attempting surgical visualization of the distal tibial plafond articular surface. Knowledge of approach specific articular surface visibility may assist the surgeon in choosing the appropriate approach(es) based on case-specific distal tibial plafond fracture patterns. LEVEL OF EVIDENCE: IV, cadaver study.

Accident Mechanisms and Injury Patterns in E-Scooter Users­A Retrospective Analysis and Comparison With Cyclists.

BACKGROUND: E-scooter sharing systems were initiated in Hamburg in June 2019. The number of persons injured in Hamburg in e-scooter accidents rose thereafter. The goal of this study was to determine the typical accident mechanisms and injury patterns after e-scooter accidents in Germany, and to compare these with bicycle accidents. METHODS: In a retrospective study, accidents with e-scooters and bicycles that occurred from June 2019 to June 2020 were registered and analyzed with respect to demography, accident mechanisms, diagnostics, patterns of injury, emergency medical care, operations, and inpatient hospitalizations. RESULTS: 89 persons sustained e-scooter accidents (mean age 33.9 years, standard deviation [SD] 14 years); 435 persons who sustained bicycle accidents (mean age 42.5 years, SD 17 years) served as a comparison group. E-scooter accidents more commonly occurred at night (37% versus 14%), and 28% of the persons who sustained them were under the influence of alcohol (cyclists: 6%). 54% of the injured e-scooter riders suffered trauma to the head or face; 14% had a severe head injury and 16% had a severe facial injury. Fractures of the upper limbs were more common than fractures of the lower limbs (18% versus 6%). On initial assessment in the emergency room, injured cyclists were more frequently classified as needing immediate treatment than injured e-scooter riders (7% versus 1%). CONCLUSION: The head, face, and upper limbs are the most commonly affected parts of the body in e-scooter accidents. Compared to bicycle accidents, e-scooter accidents more commonly occur on weekends and in association with alcohol. From a medical point of view, abstaining from alcohol consumption and wearing a helmet when using an e-scooter is strongly recommended.

Total Hip Arthroplasty in a Patient with Mucopolysaccharidosis Type IVB.

Introduction. Morquio syndrome or mucopolysaccharidosis (MPS) type IV is a rare autosomal recessive lysosomal storage disease, characterized by abnormal metabolism of glycosaminoglycans associated with specific skeletal deformities, also known as dysostosis multiplex. Case Presentation. We present the case of a 23-year-old patient with advanced osteonecrosis of the femoral head (ONFH) on both sides due to Morquio syndrome. A diagnosis of mucopolysaccharidosis type IVB was made after extensive genetic profiling. The patient had the condition for a long time. At 7 years old, the patient was treated with bilateral pelvic Salter's osteotomy. Afterward, the patient was able to walk freely but could never take part in sports. At 22 years old, pain in the hip increased, and magnetic resonance imaging showed a bilateral femur head necrosis. Hence, the patient underwent cementless total hip arthroplasty (THA). Intraoperatively, a periprosthetic fracture occurred. Therefore, revision surgery with internal fixation was performed on the next day. Postoperatively, a weight-bearing restriction of 20 kg on the left leg was imposed for 6 weeks. The patient made a full recovery and was able to move without residual complaints. Annual orthopedic evaluation in patients treated with surgical intervention is recommended. Discussion. Orthopedic challenges for mucopolysaccharidoses and corresponding bone alterations, known as dysostosis multiplex, involving trunk and limbs with typical radiological findings have been well described. The hip is invariably involved, with dysplasia affecting the femoral neck (coxa valga), femoral epiphysis (loss of sphericity, osteonecrosis), and a flared hypoplastic iliac wing. Symptomatic therapy consists, on the one hand, of a surgical procedure and, on the other hand, a variety of supportive measures. However, the management of joint replacement in lysosomal storage diseases has not been well reported. All patients with MPS should be considered at high risk for surgical intervention requiring anesthesia because of airway and cardiac disease manifestations. In the case of a need for THA, we recommend cemented stem fixation because of the overall poor bone quality in patients with Morquio syndrome.

Circulating growth/differentiation factor 15 is associated with human CD56bright natural killer cell dysfunction and nosocomial infection in severe systemic inflammation.

BACKGROUND: Systemic inflammation induced by sterile or infectious insults is associated with an enhanced susceptibility to life-threatening opportunistic, mostly bacterial, infections due to unknown pathogenesis. Natural killer (NK) cells contribute to the defence against bacterial infections through the release of Interferon (IFN) γ in response to Interleukin (IL) 12. Considering the relevance of NK cells in the immune defence we investigated whether the function of NK cells is disturbed in patients suffering from serious systemic inflammation. METHODS: NK cells from severely injured patients were analysed from the first day after the initial inflammatory insult until the day of discharge in terms of IL-12 receptor signalling and IFN-γ synthesis. FINDINGS: During systemic inflammation, the expression of the IL-12 receptor ß2 chain, phosphorylation of signal transducer and activation 4, and IFN-γ production on/in NK cells was impaired upon exposure to Staphylococcus aureus. The profound suppression of NK cells developed within 24 h after the initial insult and persisted for several weeks. NK cells displayed signs of exhaustion. Extrinsic changes were mediated by the early and long-lasting presence of growth/differentiation factor (GDF) 15 in the circulation that signalled through the transforming growth factor ß receptor I and activated Smad1/5. Moreover, the concentration of GDF-15 in the serum inversely correlated with the IL-12 receptor ß2 expression on NK cells and was enhanced in patients who later acquired septic complications. INTERPRETATION: GDF-15 is associated with the development of NK cell dysfunction during systemic inflammation and might represent a novel target to prevent nosocomial infections. FUND: The study was supported by the Department of Orthopaedics and Trauma Surgery, University Hospital Essen.

Invasive Surgery Impairs the Regulatory Function of Human CD56 bright Natural Killer Cells in Response to Staphylococcus aureus. Suppression of Interferon-γ Synthesis.

Major surgery increases the risk for infectious complications due to the development of immunosuppression. CD56 bright NK cells play a key role in the defense against bacterial infections through the release of Interferon (IFN) γ upon stimulation with monocyte-derived Interleukin (IL) 12. We investigated whether invasive visceral surgery interferes with the IFN-γ synthesis of human NK cells in response to Staphylococcus aureus. In a prospective pilot study, peripheral blood mononuclear cells (PBMC) were isolated from 53 patients before and 1 to 7 d after elective visceral surgery. The release of IL-12 and IFN-γ from PBMC upon exposure to S. aureus in vitro was quantified. The expression of the IL-12 receptor ß1 chain on the surface, the phosphorylation of signal transducer and activator of transcription (STAT) 4, and the synthesis of IFN-γ on/in individual CD56 bright NK cells were investigated using flow cytometry. The modulatory effect of IL-12 on the S. aureus-induced IFN-γ production in CD56 bright NK cells was analyzed. The IFN-γ secretion from purified CD56 bright NK cells was quantified after stimulation with IL-12 and IL-18. After surgery, CD56 bright NK cells among total PBMC were impaired in the release of IFN-γ for at least 5 d. Likewise, the IL-12-induced release of IFN-γ from purified CD56 bright NK cells was abolished. Upon stimulation with S. aureus, PBMC secreted less IL-12 but supplementation with recombinant IL-12 did not restore the capacity of CD56 bright NK cells to produce IFN-γ. CD56 bright NK cells displayed reduced levels of the IL-12Rß1 chain whereas the phosphorylation of STAT4, the key transcription factor for the Ifng gene was not diminished. In summary, after invasive visceral surgery, CD56 bright NK cells are impaired in S. aureus-induced IFN-γ production and might contribute to the enhanced susceptibility to opportunistic infections.